Peacekeeping force language

An Italian friend was walking in a park, carrying his young son, a baby, in his arms, in a bundle in front of his chest. He came across a bunch of young boys kicking a ball, and it so happened that the ball came his way, so he decided to kick it back to the boys. He did not do this particularly well, or rather too well, and managed to hit the boy who came running for the ball straight in his face. No big harm had been done but the boy immediately started crying and making a fuss. My friend immediately stepped forward to soothe the boy, trying out both his French and his German on him, the whole story happening in Luxemburg. To no avail. The boy continued crying his heart out. At that moment the boy’s mother approached, furious, giving my friend a hard time and scolding him for what he had done to her beloved son. Again, he tried to apologise and make her see that no big harm had been done. To no avail. Then, all of a sudden, he heard the boy speak to his mother, and it turned out that he was speaking Italian to her. Both the boy and the mother were Italian. Immediately, things calmed down, the boy calmed down, the mother calmed down, and they fell into a friendly, lively conversation about the world and his wife, in Italian.